Copper: Demonic Conflict is the fourth Secret Mission in DmC: Devil May Cry. In this, Dante must defeat all 2 Shielded Bathos and 3 Death Knights using only Demonic weapons Eryx and Arbiter within 80 seconds.
It is recommended to break the shield of the Death Knights first hacking them away with heavy attacks. Dante should also pull the Shielded Bathos from the ground as Eryx and Arbiter are more suited for ground combat. Utilizing Demon Evade can greatly help in completing the secret mission.